The present invention relates to the field of homogenizing apparatuses.
The homogenization process has the function of reducing the dimensions of the drops of an emulsion, or of the particles of a suspension, and to make them as homogeneous and identical to each other as possible. The homogenization process generally comprises the passage (blow-by) of the fluid to be homogenized, under appropriate pressure, through a nozzle or a very narrow passage, to cause impacts and subdivisions of the particles; preferably, the flow of particles exiting at high speed from said passage is made to impact against an obstacle located at a short distance from the passage, which further contributes to reduce the dimensions of the particles and improve homogenization.
In this field the Applicant has already obtained the Italian patent IT 1.282.765, and filed the corresponding European patent application, publication EP 0.810.025, with the disclosure of an improved homogenization valve.
Essentially, the aforesaid valve comprises two consecutive coaxial annular chambers, separated by a nozzle with radial profile whose height is governed by a pressure means acting in the axial direction against a piston sliding axially within said chambers whereof it defines the radially interior wall: this valve allows to use high pressures for feeding the fluid to be homogenized, to over 1000 bar, minimizing the force needed to maintain the dimensions of the nozzle, whilst providing a product with high quality characteristics. The Applicant has now set the goal of increasing the flow rate of the valve whilst maintaining all other conditions equal, i.e. without increasing the size of the valve and the applied pressure, maintaining constant or improving the efficiency of the homogenization, i.e. the quality of the final product.
The problem is not an easy one to solve because it is not possible simply to increase the size of the nozzles, nor is it sufficient to multiply their number, since both these measures either fail to achieve the desired result or compromise the quality characteristics of the finished product or unacceptably raise the cost of the valve. In particular, in the case of an increase in the number of nozzles, the degree of homogenization and the consistency of the result are compromised because it is impossible to maintain the same fluid feeding pressure: this inequality of pressure also causes, over time, a different degree of wear of the different nozzles, with variation in their section and in the fluid-dynamic characteristics of the traversing flow. The consequences are the impossibility of keeping the phenomenon under control and an unacceptable degradation of the quality characteristics of the homogenized.
The Applicant has now defined a plurality of construction elements of the valve and identified a series of critical relationships between said construction elements which allow to obtain the sought result.